Jenson Button managed to pip Nico Rosberg for the fastest time in Friday's second practice session for the Turkish Grand Prix, with Lewis Hamilton third in front of Michael Schumacher and Mark Webber.

The world champion, Sebastian Vettel, did not run in the afternoon because in the much wetter morning session, in which Fernando Alonso was fastest, he crashed into the barriers after running wide at turn eight, with the car sustaining significant damage. It leaves Vettel with only 60 minutes of running in Saturday's final session to acclimatise himself to the circuit before the qualifying showdown.

"My information is that we are in pretty good shape in terms of getting the car ready in time," the team principal, Christian Horner, said.

A number of drivers had difficulties when the rain started to fall heavily, with a little over half an hour remaining of the earlier run. But when the track turned dry later in the day the McLarens looked the fastest cars although Felipe Massa, three times a winner here, also put in a fast time and was sixth in the session.

Button and his McLaren team-mate Hamilton dominated the early stages of the afternoon before the German pair of Rosberg and Schumacher showed their pace.

For Button, who has not won a race for over a year but who triumphed here in 2009 and was second last year, this was an encouraging performance.

But the problems at Williams continued, with Pastor Maldonado coming off the track a number of times and Rubens Barrichello coming 16th.